fix(cli): assess transformer version in data assessor (#14896)

fix(cli-internal): assess transformer version in data assessor

DataAssessor now checks graphQLTransformer.transformerVersion via
FeatureFlags. If the version is not 2, the resource is recorded as
unsupported with a clear note. This prevents Gen2 migration from
proceeding on Transformer V1 projects.

Snapshot tests (generate, refactor) initialize FeatureFlags from the
app's cli.json via MigrationApp.run, so no mocking is needed there.
Unit tests use a strict jest.spyOn that only responds to the expected
flag name and throws on any other call.

---
Prompt: Look at the changes I made and write a unit test in
data.assessor.test.ts

Author: iliapolo

docs/packages/amplify-cli/src/commands/gen2-migration/assess.md

@@ -76,7 +76,7 @@ Produced by `Gen1App.discover()`. The `key` field is a typed `category:service`
 | auth      | Cognito-UserPool-Groups | ✔                | ✔           |
 | storage   | S3                      | ✔                | ✔           |
 | storage   | DynamoDB                | ✔                | ✔           |
-| api       | AppSync                 | ✔                | n/a         |
+| api       | AppSync                 | ✔ (V2 only)      | n/a         |
 | api       | API Gateway             | ✔                | n/a         |
 | analytics | Kinesis                 | ✔                | ✔           |
 | function  | Lambda                  | ✔ (Node.js only) | n/a         |
@@ -89,5 +89,5 @@ Produced by `Gen1App.discover()`. The `key` field is a typed `category:service`
 - Adding a new resource type: add the pair to `KNOWN_RESOURCE_KEYS` in `gen1-app.ts`, create an assessor, handle the case in `assess.ts`, and in the generate/refactor steps. The compiler enforces exhaustiveness.
 - The `Assessment` is also used by generate and refactor steps for validation — `validFor(step)` returns false if any resource or feature is unsupported for that step. The `of(resource, step)` method returns the `Support` for a specific resource, used by the generate orchestrator to skip unsupported resources before instantiating generators.
 - Feature detection (overrides, custom policies, conflict resolution) is assessor-specific. Each assessor checks for files in the cloud backend directory via `gen1App.fileExists()` or reads `cli-inputs.json` via `gen1App.cliInputs()`.
-- `DataAssessor` detects conflict resolution (DataStore) by reading `cli-inputs.json` for the API resource. If `serviceConfiguration.conflictResolution` is present and non-empty, both generate and refactor are marked unsupported because Gen2 does not support DataStore conflict resolution.
+- `DataAssessor` checks the GraphQL transformer version via `FeatureFlags.getNumber('graphQLTransformer.transformerVersion')`. If the version is not 2 (i.e., Transformer V1), the resource is marked unsupported for generate. It also detects conflict resolution (DataStore) by reading `cli-inputs.json` for the API resource. If `serviceConfiguration.conflictResolution` is present and non-empty, both generate and refactor are marked unsupported because Gen2 does not support DataStore conflict resolution.
 - `FunctionAssessor` reads the Lambda runtime from the local CloudFormation template (`function/<name>/<name>-cloudformation-template.json`). Non-Node.js runtimes are marked as unsupported for generate. Function refactor is always not-applicable since functions are stateless.

packages/amplify-cli/src/__tests__/commands/gen2-migration/_framework/app.ts

@@ -7,7 +7,7 @@ import { SpinningLogger } from '../../../../commands/gen2-migration/_common/spin
 import { Gen1App } from '../../../../commands/gen2-migration/_common/gen1-app';
 import { AwsFetcher } from '../../../../commands/gen2-migration/_common/aws-fetcher';
 import { AwsClients } from '../../../../commands/gen2-migration/_common/aws-clients';
-import { JSONUtilities } from '@aws-amplify/amplify-cli-core';
+import { JSONUtilities, FeatureFlags } from '@aws-amplify/amplify-cli-core';
 import { Snapshot } from './snapshot';
 import { DEFAULT_STATEFUL_RESOURCES } from '../../../../commands/gen2-migration/_common/resource-types';
 
@@ -398,6 +398,7 @@ export class MigrationApp {
 
     process.chdir(workDir);
     try {
+      await FeatureFlags.initialize({ getCurrentEnvName: () => app.environmentName });
       await callback(app);
     } finally {
       process.chdir(cwd);

packages/amplify-cli/src/__tests__/commands/gen2-migration/assess/api/data.assessor.test.ts

@@ -1,6 +1,7 @@
 import { DataAssessor } from '../../../../../commands/gen2-migration/assess/api/data.assessor';
 import { Assessment } from '../../../../../commands/gen2-migration/assess/assessment';
 import { Gen1App, DiscoveredResource } from '../../../../../commands/gen2-migration/_common/gen1-app';
+import { FeatureFlags } from '@aws-amplify/amplify-cli-core';
 
 // eslint-disable-next-line @typescript-eslint/no-explicit-any -- test helper for untyped cli-inputs.json
 function mockGen1App(existingFiles: string[] = [], cliInputsData: any = {}): Gen1App {
@@ -12,10 +13,22 @@ function mockGen1App(existingFiles: string[] = [], cliInputsData: any = {}): Gen
   } as unknown as Gen1App;
 }
 
+function mockTransformerVersion(version: number): void {
+  jest.spyOn(FeatureFlags, 'getNumber').mockImplementation((flagName: string) => {
+    if (flagName === 'graphQLTransformer.transformerVersion') return version;
+    throw new Error(`Unexpected FeatureFlags.getNumber call: ${flagName}`);
+  });
+}
+
 const RESOURCE: DiscoveredResource = { category: 'api', resourceName: 'myApi', service: 'AppSync', key: 'api:AppSync' };
 
 describe('DataAssessor', () => {
+  afterEach(() => {
+    jest.restoreAllMocks();
+  });
+
   it('records resource as supported', () => {
+    mockTransformerVersion(2);
     const assessment = new Assessment('app', 'dev');
     new DataAssessor(mockGen1App(), RESOURCE).record(assessment);
 
@@ -25,6 +38,7 @@ describe('DataAssessor', () => {
   });
 
   it('detects override.ts', () => {
+    mockTransformerVersion(2);
     const assessment = new Assessment('app', 'dev');
     new DataAssessor(mockGen1App(['api/myApi/override.ts']), RESOURCE).record(assessment);
 
@@ -37,13 +51,15 @@ describe('DataAssessor', () => {
   });
 
   it('records no features when override.ts is absent', () => {
+    mockTransformerVersion(2);
     const assessment = new Assessment('app', 'dev');
     new DataAssessor(mockGen1App(), RESOURCE).record(assessment);
 
     expect(assessment.features).toHaveLength(0);
   });
 
   it('detects conflict resolution (DataStore) as unsupported', () => {
+    mockTransformerVersion(2);
     const cliInputs = {
       version: 1,
       serviceConfiguration: {
@@ -66,6 +82,7 @@ describe('DataAssessor', () => {
   });
 
   it('does not record conflict resolution when it is absent from cli-inputs.json', () => {
+    mockTransformerVersion(2);
     const cliInputs = {
       version: 1,
       serviceConfiguration: {
@@ -81,6 +98,7 @@ describe('DataAssessor', () => {
   });
 
   it('does not record conflict resolution when conflictResolution is an empty object', () => {
+    mockTransformerVersion(2);
     const cliInputs = {
       version: 1,
       serviceConfiguration: {
@@ -94,4 +112,25 @@ describe('DataAssessor', () => {
 
     expect(assessment.features).toHaveLength(0);
   });
+
+  it('records resource as unsupported when transformer version is not 2', () => {
+    mockTransformerVersion(1);
+    const assessment = new Assessment('app', 'dev');
+    new DataAssessor(mockGen1App(), RESOURCE).record(assessment);
+
+    const entry = assessment.resources[0];
+    expect(entry!.generate.level).toBe('unsupported');
+    expect(entry!.generate).toHaveProperty('note', 'Transformer V1 is not supported in Gen2');
+    expect(entry!.refactor.level).toBe('not-applicable');
+  });
+
+  it('records resource as supported when transformer version is 2', () => {
+    mockTransformerVersion(2);
+    const assessment = new Assessment('app', 'dev');
+    new DataAssessor(mockGen1App(), RESOURCE).record(assessment);
+
+    const entry = assessment.resources[0];
+    expect(entry!.generate.level).toBe('supported');
+    expect(entry!.refactor.level).toBe('not-applicable');
+  });
 });

packages/amplify-cli/src/commands/gen2-migration/assess/api/data.assessor.ts

@@ -1,10 +1,11 @@
 import { Assessor } from '../assessor';
 import { Assessment, supported, unsupported, notApplicable } from '../assessment';
 import { Gen1App, DiscoveredResource, KNOWN_FEATURES } from '../../_common/gen1-app';
+import { FeatureFlags } from '@aws-amplify/amplify-cli-core';
 
 /**
  * Assesses migration readiness for an AppSync GraphQL API resource.
- * Detects overrides.ts usage and conflict resolution (DataStore).
+ * Rejects Transformer V1 projects, detects overrides.ts usage and conflict resolution (DataStore).
  */
 export class DataAssessor implements Assessor {
   public constructor(private readonly gen1App: Gen1App, private readonly resource: DiscoveredResource) {}
@@ -14,7 +15,17 @@ export class DataAssessor implements Assessor {
    */
   public record(assessment: Assessment): void {
     this.gen1App.ensureCliInputs(this.resource.category, this.resource.resourceName);
-    assessment.recordResource({ resource: this.resource, generate: supported(), refactor: notApplicable() });
+
+    const transformerVersion = FeatureFlags.getNumber('graphQLTransformer.transformerVersion');
+    if (transformerVersion !== 2) {
+      assessment.recordResource({
+        resource: this.resource,
+        generate: unsupported('Transformer V1 is not supported in Gen2'),
+        refactor: notApplicable(),
+      });
+    } else {
+      assessment.recordResource({ resource: this.resource, generate: supported(), refactor: notApplicable() });
+    }
 
     const overridesPath = `api/${this.resource.resourceName}/override.ts`;